Equine mask

ABSTRACT

A mask is provided for administering medication, particularly asthmatic medication, to equine animals, particularly horses. The mask has a body that fits over the nostrils of the horse. An aerosolization chamber is secured to the body and opens into the interior thereof, and is supplied with misted medications such as from a metered dose inhaler, for inhalation by the animal. The mask and body is also provided with one or more exhalation ports, and a strap or band or the like for securing the body to the animals face overlying the nostrils.

CROSS REFERENCE TO RELATED APPLICATION

[0001] This application is a continuation of application Ser. No.07/947,821, filed Sep. 24, 1992, which is incorporated herein byreference, which is a continuation-in-part of application Ser. No.07/776,835, filed Oct. 15, 1991, which is now abandoned.

BACKGROUND OF THE INVENTION

[0002] Many people suffer breathing problems, particularly asthma, fromallergic reactions. Asthma is frequently triggered by grasses, grains,and dust. Alternatively, wet materials, particularly molds often triggerasthmatic attacks. Much work has been done to ameliorate asthmaticattacks in human beings. Metered dose inhalers (MDI) have been developedwhich will deliver a metered does of medication upon depression of anoutlet valve. Epinephrine was one of the first such anti-asthmatic drugsto be packaged in metered dose inhalers. However, epinephrine hasundesirable side effects, and better medications have been developed,such as metaproterenol, and albuterol. These have a more direct actionon the bronchi and do not have nearly as many side effects.

[0003] The metered dose inhalers do not themselves produce asufficiently aerosolized form of medication to be highly effective.Various efforts have been made to provide chambers between the metereddose inhalers and the users, say for example Nowacki et al U.S. Pat. No.4,470,412, and Foley et al U.S. Pat. No. 5,012,803. The aerosolizingchambers disclosed and claimed in the two foregoing patents arerelatively inexpensive and highly effective in producing more efficientuse of the medication.

[0004] There is another class of sufferers of asthma that has not as yetbeen given adequate attention. Members of the equine family often sufferfrom asthma. For example, it is estimated that there are 10,000,000horses in the United States. It is further estimated that 60% of thehorses are asthmatic. This means that there are something on the orderof 6,000,000 asthmatic horses in the United States alone. Althoughprospectively one does not tend to think of horses and other animals ofthe equine family as being sufferers of asthma, it would be appreciatedthat such animals are constantly around grasses, grains, dust, molds,etc. which are recognized allergens. The problem is particularly acutewith horses that have to perform physically, such as race horses,working farm horses, etc. Some little work has been done withnebulizers, but these have not been very effective. Furthermore, it isbelieved that there is no anti-asthmatic medication with specialefficacy in the equine family. Further, it is believed that it will bemany years before any such specific anti-asthmatic medication isdeveloped. However, we have found that human type anti-asthmaticmedications are effective with horses and the like.

[0005] The problem is to deliver anti-asthmatic medication to equineanimals. It is true that horses can be taught some tricks, and certainworking activities, but there is no evidence to indicate that a horsecan be told when to inhale, and when to hold its breath, etc.

OBJECTS AND SUMMARY OF THE PRESENT INVENTION

[0006] It is an object of the present invention to provide a deliverysystem for supplying asthmatic medication to members of the equinefamily.

[0007] More particularly, it is an object of the present invention toprovide an equine mask cooperable with a modular medication inhaler asdisclosed and claimed in the aforesaid Foley et al U.S. Pat. No.5,012,803 for supplying anti-asthmatic medication to equine animals.

[0008] Further objects include the provision of a mask which is readilyattached over the nostrils and mouth of an equine animal, which mask hasprovision for causing the animal to gasp, and thereby draw in moremedication, and which mask further has a visible exhalation valve sothat one may observe the breathing pattern of such an animal.

[0009] In carrying out the foregoing and other objects of the presentinvention we take advantage of the fact that horses are accustomed tohaving devices placed over their mouths and adjacent portions of thehead, feedbags being common examples. We provide a mask covering thenostrils and mouth of a horse which is lightly sealed to the adjacentareas of the horse's head, but allowing a certain amount of air to passunder the seal along the horse's mouth, as this is comforting to thehorse; FIG. 21 is a view generally similar to FIG. 6, but showing amodification using a nebulizer rather than a metered dose inhaler; andFIG. 22 is a fragmentary view showing a modification of a portion ofFIG. 21. Either the mask is readily attached to the horse or otherequine animal by means of attachments secured to the normal harness ofthe horse, or by means of a strap, such as one embodying hook and loopfasteners (Viz., VELCRO). An aerosolizing chamber as previously noted inaccordance with U.S. Pat. No. 5,012,803 is secured to the mask,preferably in a horizontal position for most effective distribution ofthe medication. Rubber flap exhalation valves are provided in the maskadjacent each nostril of the horse or the like, with the flaps of theexhalation valves readily visible so that the breathing pattern of thehorse can be observed. The aerosolizing chamber is connected to the maskby a bypass passageway which enables the owner or veterinarian tocontrol to some extent the inhalation of the horse or the like, therebyproducing gasping to clear the airways, and to pull in the medication.

[0010] A knob canopy also is provided on the mask which is readilygrasped by the hand of an owner or veterinarian in order properly toposition the mask relative to the nostrils and the mouth of the animal.

THE DRAWINGS

[0011] The present invention will best be understood from the followingspecification when taken in connection with the accompanying drawingswherein:

[0012]FIG. 1 is a side view of the front end of a horse with the mask,etc. of the present invention in place;

[0013]FIG. 2 is a front view of the horse and mask of FIG. 1 on aslightly enlarged scale;

[0014]FIG. 3 is an enlarged side view partially in section of themetered dose inhaler and the aerosolization chamber;

[0015]FIG. 4 is a detail of a modification of a portion of FIG. 3;

[0016]FIG. 5 is a detail similar to FIG. 4 of a further modification;

[0017]FIG. 6 is a view generally similar to FIG. 1 showing a preferredform of the invention;

[0018]FIG. 7 is an axial view of the gasket for fitting the mask to thehorse;

[0019]FIG. 8 is a sectional view through the gasket of FIG. 7 as takensubstantially along the line 8-8 in FIG. 7;

[0020]FIG. 9 is a perspective view of a supplementary inhalation devicejoining the aerosolization chamber to the mask;

[0021]FIG. 9A is a perspective view of a portion of the supplementaryinhalation area of FIG. 9;

[0022]FIG. 9B is a perspective view of the remaining portion of thesupplementary inhalation device of FIG. 9;

[0023]FIG. 10 is a fragmentary view of the front portion of the horse'shead with a modification of the invention applied thereto;

[0024]FIG. 11 is a view generally similar to FIG. 10, but showing amodification of the invention;

[0025]FIG. 12 is another view similar to FIG. 10 showing a furthermodification of the invention;

[0026]FIG. 13 is a view of the mask and cooperating parts of FIG. 12showing an air bulb for blowing up the seal of the gasket to the horse;

[0027]FIG. 14 is a view generally similar to FIG. 10 showing amodification of the invention applied only to the horse's nostrils, andwith the mouth held shut;

[0028]FIG. 15 is a front view of the invention as illustrated in FIG.14;

[0029]FIG. 16 is a top view form of the invention shown in FIG. 15;

[0030]FIG. 17 is a view generally similar to FIG. 10 and showing anotherembodiment of the invention;

[0031]FIG. 18 is a fragmentary view of the seal for the mask;

[0032]FIG. 19 is a modification of the embodiment of the invention shownin FIG. 14:

[0033]FIG. 20 is a sectional view taken substantially along the line20-20 in FIG. 19;

[0034]FIG. 21 is a view generally similar to FIG. 6, but showing amodification using a nebulizer rather than a metered dose inhaler;

[0035]FIG. 22 is a fragmentary view showing a modification of a portionof FIG. 21;

[0036]FIG. 23 is a preferred form of the equine mask that has evolved toproduction status, and comprising a perspective view;

[0037]FIG. 24 is a side view of the mask shown in FIG. 23;

[0038]FIG. 25 is a view of a portion of a mask that fits over the frontportion of the horse's head, not including the various fittingsadaptable thereto;

[0039]FIG. 26 is a perspective view of a M.D.I. (metered dose inhaler)plate for attachment to the mask;

[0040]FIG. 27 is perspective view of an adapter plate for securement tothe plate shown at the left or front portion of the mask in FIG. 25;

[0041]FIG. 28 is a perspective view similar to FIG. 25, with the plateof FIG. 27 mounted thereon;

[0042]FIG. 29 is a perspective view of an adapter plate generallysimilar to that in FIG. 27, on a smaller scale, but with a dry powderadapter plate to accept a metered dose dry powder inhaler;

[0043]FIG. 30 is a perspective view of a mask with a different adapterplate thereon, specifically an oxygen dilutor unit;

[0044]FIG. 31 is a view similar to FIG. 23, but with an air filter plateattached to the mask;

[0045]FIG. 32 is a perspective view of an adapter plate generallysimilar to FIG. 27, but on a somewhat enlarged scale, and showingfurther details of the exhalation valves;

[0046]FIG. 33 is an exploded view of the valve just noted in connectionwith FIG. 32; and

[0047]FIG. 34 is an exploded perspective view generally similar to FIG.33, but with the parts inverted relative to FIG. 33.

DETAILED DISCLOSURE OF THE ILLUSTRATED EMBODIMENTS

[0048] a. First Embodiment (FIG. 1-3)

[0049] Reference now should be made in greater particularity to thedrawings, and first to FIGS. 1 and 2 wherein there is shown the frontportion of a horse 32 including the head 34. A harness 36 of aconventional nature is applied over the horse's head. A mask or bag 38is placed over the nostrils and over the mouth 40 of the horse. The mask38 has a surrounding band 42 adjacent the upper edge thereof, andsuitable links 44 are secured to this band and are received over aportion of the harness 36 to hold the mask in place. The band 42 is ofthe size to fit snuggly about the horse's head just above the mouth andnostrils, and the size may vary depending on the type of horse and theindividual animal. The mask 38 may be molded resinous plastic material,and this may be reinforced with a cloth or webbing. The mask must besomewhat flexible, but it must also have sufficient rigidity to preventcollapse against the horse's nostrils upon inhaling.

[0050] The mask is provided with two one way exhalation valves 46. Thesemay be flap valves for suitable external clearance to allowed outwardflexing thereof upon exhalation, and backed by a spider to be closedupon inhalation. The valves 46 are respectively adjacent the horse'snostrils for minimum interference with exhalation.

[0051] A medication aerosolization inhaler 48 extends forwardly from thelower front portion of the mask 38, and communicates with the interiorof the mask to permit inhalation by the horse of medication as the horseinhales. The construction of this inhaler is structurally substantially,and functionally identical with the inhaler shown in Foley et al U.S.Pat. No. 5,012,803. The inhaler 48 includes a cylindrical body 50 whichhas an open upstream, inlet or entering end 52, and a downstream or exitend 54. An inlet fitting 56 is secured to the inlet end 52 of thecylinder 50 by means of a concentric pair of cylindrical flanges 58fitting respectively inside and outside of the entering end 52 of thebody 50. The inlet fitting 56 includes a well 60 which receives ametered dose inhaler canister 62. The fitting includes a lateralpassageway 64 for conducting medication 66 from the canister into theinhaler body 50. The lower end of the canister is provided with a nozzle68 which impinges against a shelf 70. When the canister 62 is presseddown in the well 60 the nozzle 68 is relatively depressed and dischargesa metered dose of the medication as indicated at 66.

[0052] At the outlet end 54 of the inhaler 48 there is an outlet fitting72 which is structurally and functionally similar to the outlet fittingin the afforesaid Foley et al U.S. patent. A portion 74 of the mask 38flares substantially conically outwardly from the fitting 72, and asurrounding ring 76 is provided where the flared portion 74 joins theremainder of the mask 38. The cylindrical body 50 of the inhaler ismolded rigid plastic material, while the inlet fitting 56 and outletfitting 72 are also molded of a suitable plastic material.

[0053] Alternatives for First Embodiment Inhaler Attachment

[0054] A modification of the attachment of the mask to the inhaler isshown in FIG. 4, this being very similar to what is disclosed in theaforesaid Foley et al U.S. patent. Certain other parts are the same asthose here to afore disclosed, and identified with similar numerals withthe addition of the suffix a. The outlet fitting 72 includes a cylinderextending in the downstream direction, and having secured at thedownstream end thereof inner and outer flanges 80 and 82, respectively,interconnected by a radial web 84. The portion 74 a at the front end ofthe mask 38 is cylindrical rather than flared, and has an internaldiameter to fit over the outside of the cylindrical portion 78, beingrecessed at 86 to fit over the flange 82, whereby the mask is anchoredto the inhaler.

[0055] A further modification is shown in FIG. 5. Similar parts againare identified by like numerals, this time with the addition of thesuffix b. In this instance there is an integral flange 82 b preferablyencircling the outlet end of the cylindrical wall 78 b. The cylindricalportion 78 b and 86 b fits over the wall 78 b and the flange 82 b in thesame manner as in FIG. 4.

[0056] b. Second Embodiment (FIGS. 6-9)

[0057] Another eariler preferred form of the invention is shown in FIGS.6-9. The horse is identical, and portions of the invention are the sameor similar to those heretofore shown and described, and in this instanceare identified by like numerals with the addition of the suffix c.

[0058] The mask 36 c is provided at the lower portion with a“dribble-section” or “slobbering cup” 88. Horses often sputter whenrelaxed, and this portion serves as a collecting place for sputteredsaliva.

[0059] The two exhalation ports 46 c are lowered slightly from theirposition in FIGS. 1 and 2, whereby the nostrils 90 of the horse arevisible in FIG. 6. A strap 92 extends from two discrete locations at thetop edge of the mask 38 c, passing behind the horse's head immediatelybehind the ears 94. The strap is provided with what might be called abuckle section 96, with opposing portions having hook and loop fasteners(Viz., VELCRO).

[0060] The upper edge of the mask is provided with a rubber seal orgasket 98 for connecting the mask to the horse. This seal or gasket isbest seen in FIGS. 7 and 8, and in outline comprises generally straightside edges 100 interconnected at the top and bottom by arcuate portions102. The seal includes a substantially flat transverse wall 104, whichhas a perpherial outer flange 106 extending at right angles from thewall 104. An inner perpherial flange 108 is parallel to the flange 106,and spaced inwardly therefrom a short distance, providing a gaptherebetween at 110. The gap 110 receives the upper or rear edge of themask, and the flanges 106 and 108 are adhesively or otherwise suitablysecured to the mask on the outer and inner surfaces thereof,respectively.

[0061] The rubber seal 98 is provided with a more-or-less centralopening shaped similar to the exterior of the mask, but shifted upwardlysomewhat therefrom, whereby the wall 104 has a greater radial dimensionat the bottom portion of the seal than it does towards the top. Theopening 112 is defined by reentrant flanges 114, 116, and 118. Theflanges, as seen in FIG. 8, form substantially a z-shape in section.

[0062] Considering FIGS. 7 and 8 along with FIG. 6, it will be seen thatthe innermost flange 118 of the re-entrant flanges presses against thehorse's muzzle. The flange 118 lies across the rear portion of the mouthof the horse. This permits air flow through the cavities on either sideof the horse's mouth, and this soothes the horse as air flows past.

[0063] The entering portion of the mask 38 c is substantially bellshaped at 120, and is connected to the exit end of the aerosolizationinhalation chamber by a supplementary inhalation area or device 122. Theexit end fitting 72 c of the chamber 48 c is essentially the same as inFIGS. 4 or 5, and the supplementary inhalation device 122 includes acylindrical body 124 with a perpherial flange 126 at the inlet end, thebody fitting over the cylindrical portion of the exit fitting. Areinforcing portion 126 of the bell shaped entering portion of the mask38 c is suitably affixed to the rear end 128 of the cylinder 124, byadhesive or by other suitable means. The reinforcing portion 126 alsosupports a knob 130 extending below the supplementary inhalation device122 to permit manual grasping thereof, and positioning of the horse'shead. The body is provided at an axially midway position with an arcuateslot 132 of approximately 180 degrees, or possibly less.

[0064] A semi-cylindrical closure or cover member 134 extends from endto end of the body 124 and encircles the body over somewhat greater than180 degrees, whereby to be retained on the body. The cover or closuremember 134 is arcuately movable about the body to uncover substantiallyall of the slot 132, to totally close the slot 132, or to have itpartially open.

[0065] The inlet fitting 56 c in this instance is similar to that in theaforesaid Foley et al U.S. patent, and a substantially L-shaped adapter36 receives the metered dose inhaler cartridge 62 for introduction ofmisted medication into the aerosolization inhaler.

[0066] When it is desired to introduce asthmatic medication into thehorse's respiratory system, the owner or a veterinarian will watch theflap valves in the exhalation ports to note the horse's breathingpattern with the slot 132 open wide. Shortly after the completion of anexhalation the owner or veterinarian depresses the metered dose inhalercartridge 62 to introduce a mist of medication into aerosolizationchamber 46 c. The cover or closure member 134 then is rotated to closethe slot 132. This makes breathing somewhat difficult for the horse, andthe horse inhales with a gasp, thus inhaling the now aerosolizedmedication. Breathing resistance tends to open up the horse's airwaysallowing for a more effective use of the medication.

[0067] As heretofore shown and described the medication aerosolizationinhaler 48 is preferably used in a horizontal position, as this producesthe best aerosolization and use of the medication. The specific form ofthe invention as shown in FIGS. 6-9 has proven by test to be thepreferred form. It will be noted that the fit of the flanges on thehorse's muzzle is with the rubber seal reversed from the position of theFIG. 8, whereby the taper of the flange 118 adapts well to the shape ofthe horse's nozzle. Additional embodiments of the invention that havebeen considered and/or tried are shown in the ensuing FIGS. 10-20.

[0068] c. Third Embodiment (FIG. 10)

[0069] An earlier form of the invention is shown in FIG. 10 which isgenerally similar to that shown in FIG. 1, et seq. Most of the parts areidentical, and are identified with the same numerals. Where there arechanges, like numerals are utilized with the addition of the suffix d.The mask 38 d is secured on the horse in similar fashion, but with astrap 138 running from a slot 140 adjacent to the upper edge of themask, the strap also being looped over a metal O-ring 142 forming a partof the harness 36. It will be understood that there is a plurality ofsuch loops and rings. In addition, the exhalation ports 46 d will beseen as positioned somewhat above the horse's nostrils 90. Although thisposition worked, the lower position shown in FIG. 6 is more effective indirect porting of the exhaled breath of the horse.

[0070] d. Fourth Embodiment (FIG. 11)

[0071] Another early embodiment of the invention is shown in FIG. 11.Again like numerals are used for identifying similar parts, this timewith the addition of the suffix e. Distinctions reside in the provisionof but a single exhalation port 48 e at the front central portion of themask 38 e. Another distinction is that the aerosolization chamber 48 eis actually built onto the top portion of the mask, and has a curveddeflecting wall 144 therein for deflecting the medication 66 e into themask adjacent the horse's nostrils. The exit or valve member 68 e isprovided with a bend therein so that the initial discharge is axial ofthe aerosolization chamber 48 e, which lies parallel to the upper frontportion of the mask 38 e. A further change is that an anchor 146 isprovided on each side of the mask with a strap 138 e thereon extendingthrough the O-ring 142 on each side. The strap preferably is providedwith a latching or buckle area 148 having opposed hook and loopfasteners (Viz., VELCRO). As in the embodiment of the FIGS. 1 and 2 andalso FIG. 10, there is a band 150 encircling the upper portion of themask to hold it in engagement with the frontal portion of the horse'shead.

[0072] e. Fifth Embodiment (FIGS. 12 and 13)

[0073] A further embodiment of the invention is shown in the FIGS. 12and 13. Generally, parts are similar to those heretofore disclosed, andsimilar parts are identified by the same or like numerals with theaddition of the suffix f.

[0074] In this form of the invention there is a rather large centralforward reinforcing area 120 f secured to the mask, and which receivesthe aerosolization chamber, the same as in FIGS. 1-3, and similar toFIG. 6. There is a single exhalation port 46 f on this reinforcingportion, aligned with the chamber 48 and somewhat above the nostrils 90.

[0075] The most significant distinction in this instance is that themask is secured by clamping to the horse's head by a strap 150 f, whichspecifically is a pneumatic tube. The tube initially is not inflated,and the mask is placed over the nostrils and mouth of the horse. Aninlet valve 152 is provided for the pneumatic tube 158. An inflater 154comprises a tube 156 with a threaded end 158 for threading into theinlet 152, and a pneumatic rubber bulb 160 at the other end, with avalve including a screw 162. The pneumatic tube is inflated to gripagainst the horse's muzzle, and a cover strip 164 covers the inlet valve152, and is secured in place by hook and loop fasteners 166.

[0076] f. Sixth Embodiment (FIGS. 14-16)

[0077] A somewhat different form of the invention is shown in FIGS.14-16. The numerals used for various portions of the horse and harnessremain identical with those previously used. Insofar as portions of themask are similar to those heretofore used, similar numerals are usedwith the addition of the suffix g. The form of the invention in FIGS.14-16 is somewhat skeletonized compared with previous embodiments. Mask38 includes a hollow body 168 with a tubular entrance end 170 extendingthereinto. The cylindrical body 48 g of the aerosolization chamber 50 gplugs directly into the tubular entrance 170 of the hollow body 168. Thesingle exhalation port 46 g is mounted on the top or frontal portion ofthe hollow body. Hollow side branches 172 extend from the body to thevicinity of the horse's nostrils 90, and substantially cylindrical cups174 extend therefrom to overlie the nostrils 90, thus establishingcommunication between aerosolizing chamber 50 g and the horse'snostrils. Exhalation is through the cups 174 and the hollow body 168 tothe exhalation port 46 g. It will be noted that adjacent the inlet endof the body 48 g there is a tapered section 176 having a plurality ofholes therein for permitting the horse to breath when no medication isbeing supplied, and for admitting air to carry the aerosolizedmedication to the horse's nostrils. In prior forms of the invention nospecific mention was made of air entrance although the structure in FIG.11 is substantially the same as in FIGS. 14 and 15. In other figuresthere is simply clearance space around the canister 62, as in well knownaerosolization chambers for humans, for example, that shown in theearlier mentioned Foley et al U.S. Pat. No. 5,012,803.

[0078] The body is provided with underlying extensions 180 having slotstherein for receipt of a strap 182 passing beneath the horse's lowerjaw. In addition, there are upward extensions 184 having slots thereinfor receipt of straps 186 passing over a portion of the harness 36.Further, there are slots 188 adjacent the front of the body for receiptof a connecting strap 190 lying across the front of the horse's muzzle.

[0079] g. Seventh Embodiment (FIGS. 17 and 18)

[0080] In the embodiment shown in FIGS. 17 and 18 many of the parts aresimilar to those previously shown and described, and are identified bylike numerals with the addition of the suffix h. A distinction residesin the fact that the mask is made of two pieces, a main body 192 whichfits fairly loosely around the horse, and a retaining section 194suitably secured thereto as by an adhesive. The retaining section 194 isresilient and is provided with a tubular inner edge which fits closelyagainst the horse. Strap 186 h is mechanically or adhesively secured at198 to the mask, and passes over a portion of the harness 36.

[0081] h. Eighth Embodiment (FIGS. 19 and 20)

[0082] Still another embodiment illustrated is that shown in FIGS. 19and 20. Certain parts are similar to those heretofore shown anddescribed, and are identified by like numerals with the addition of thesuffix i. In this instance the mask 36 i is provided with an extension200 which houses the aerosolization chamber 48 i. It opens directly intothe mask, which is spaced somewhat above the muzzle of the horse, and inthe vicinity of the nostrils 90. A single exhalation valve 46 i isprovided. An extension 202 on the rear or lower portion of the mask hasa fixed anchor 204 thereon, and a strap 206 extends beneath the horse'sjaw and to a similar anchor on the opposite side.

[0083] Another fixed anchor 208 is provided on the lower rear portion ofthe mask, and a strap 210 extends therefrom to a like anchor on theopposite side. The two straps 206 and 210 hold the mask over the horse'snostrils. Horses are known to be nose or nostril breathers, and hencethe coverage of the mouth is not essential.

[0084] i. Ninth Embodiment (FIGS. 21 and 22)

[0085] A further embodiment of the invention is shown in FIG. 21 inwhich a nebulizer is used rather than a metered dose inhaler (MDI). Manyof the parts are identical with those heretofore disclosed and areidentified by the same numerals. Similar parts are identified by similarnumerals with addition of the suffix j.

[0086] The mask 38 j is functionally the same as the mask 38 c in FIG.6, and structurally similar thereto. The knob 130 j has been moved tothe slobbering cup area 88 j where is somewhat more accessible. Theexhalation parts or one-way exhalation valve 46 j are drawn somewhatdifferently to show the rubber flap valve 212.

[0087] The important distinction is that a corrugated aerosol tube orhose 214 is connected to the front center of the mask 38 j adjacent thehorse's nostrils. The inlet or upstream end of the tube or hose 214 isconnected to and supplied from a nebulizer 216 which in turn is suppliedthrough a tube 218 with air from an air compressor 220. A few cc ofsaline solution are placed manually in the nebulizer 216.

[0088] Different types of nebulizers are known, and the nebulizer may beany suitable known or conventional type of nebulizer. Indeed, as shownin FIG. 22 an ultrasonic nebulizer 222 may be substituted for thenebulizer 216, the tube 218, and the air compressor 220. The ultrasonicnebulizer 222 is directly connected to the corrugated tube 214.

[0089] Considerations Applicable to First Through Ninth Embodiments

[0090] Some veterinarians and/or owners are more familiar withaerosolized water (preferably saline) vapor than with aerosolizedasthmatic medication from an MDI. Either aerosolized asthmaticmedication or aerosolized (saline) water vapor can be considered to be abreathing enhancement vapor, and either can provide a measure ofasthmatic relief.

[0091] Although certain materials have been suggested for constructionof the equine mask, the preferred construction material is a moldedacrylic resin. It is substantially rigid, but with a certainflexibility. Further, it is quite strong. This is helpful, in that it isquite possible that the mask could be dropped and stepped on by thehorse, and it is desirable that is should not be destroyed by such anaccident.

[0092] It will be appreciated that standardbred horses and thoroughbredhorses, and other breeds tend to be of different sizes, and evenindividual specimens within a given breed may differ significantly insize. Hence, the mask may have to differ somewhat in size or relativedimensions depending on the horse on which it is to be used. Further, itshould be borne in mind that a separate mask should be used for eachhorse to avoid dangers of cross contamination. Preferably, the entrancearea to the mask should be bell shaped, and there should be a“dribble-section” or “slobbering-cup” formed as a part of the bottom ofthe mask as heretofore noted. Generally speaking, the anti-asthmaticmedication can be a beta agonist. Specific forms of anti-asthmatic drugshave been noted heretofore, and it also be noted the corticosteroids areuseful in combating asthmatic attacks.

[0093] It has been noted that there should not be an air tight seal. Thecavities on either side of the horse's mouth soothes the horse as airflows past. With the specific reference to the preferred form of theinvention in FIGS. 6-9, the silicone seal was found to work better withthe innermost lip or fold 118 pointing in toward the interior of themask, i.e. toward the end of the horse's muzzle. The mask should createsome resistance to breathing for the horse, as this tends to open theairways, allowing for a more effective use of the medication.

[0094] Reference has been made to one-way flap valves for the exhalationport. These are not shown in detail, since they are well known, see forexample the flap valves in the U.S. Pat. No. 4,470,412 to Nowacki et aland to Foley et al U.S. Pat. No. 5,012,803.

[0095] Dead space within the mask is not a major factor, because of thesize of the tidal volume of a horse, typically between 3 and 7 liters. Ahorse's inhalation flow rate is generally between 5 and 10 liters persecond. It is preferred to have the aerosolization chamber in ahorizontal position, and to have it as low as possible, since the horsewill have a tendency to raise its head. Generally speaking, the horsewill move its head in a vertical plane, rather than in a horizontalplane. Two breaths of the horse should be allowed between puffs ofmedication, and the overall time for administering the anti-asthmaticmedication is estimated to be in the order of 5 to 10 minutes. It willbe apparent that care must be taken in applying the mask so that it doesnot in any way obstruct the nostrils of the horse. As is known amonghorse people, it is best to approach a horse from the left side.

[0096] It has been noted above that the mask may have to differ in sizefrom one horse to another, and dimensions that have measured by way ofexample include 5 to 6 inches across the sealing area, with thecircumference of this sealing area running from 20 to 23 inches.

[0097] The supplying of anti-asthmatic medication to horses isapplicable to all types. It will improve the performance of sportshorses, such as race horses and jumpers, but it will also improve theperformance of working type horses. The embodiments of the invention asherein shown and described will be understood as being exemplary.

[0098] j. Tenth Embodiment (FIGS. 23-26)

[0099] A preferred form of the equine mask has now evolved. Such mask isshown in FIG. 23 et seq. The mask is molded of a superior modernplastic. An acrylic plastic is satisfactory for most purposes, and isreasonably inexpensive. However, where hard use is expected such aswhere the mask might be in a stable or the like where it could bedropped and stepped on by a horse polycarbonate plastic is preferred. Inany event, the mask is generally rigid, but is somewhat bendable. In thecase of a mask molded of polycarbonate plastic, the plastic willwithstand rather considerable deformation without significant damage.The forward part of the mask is clear plastic so that the horse'snostrils, lips, and adjacent parts can be observed by a personadministrating medication. The rear portion is cloudy as visiontherethrough is not necessary, and helps to focus the attention of theadministrating person on the important area of the horse's head.Furthermore, scratches and other marks show less on the cloudy portion.The equine mask now to be described in detail is more durable,repairable, versatile and cleanable.

[0100] Turning first to FIGS. 23-25, similar parts are again identifiedby like numerals, this time with the addition of the suffix k. The mask38 k has a gasket 98 k at the upper or rear portion thereof. The frontportion of the mask is clear at 224 so that the horse's nostrils, andpreferably also his lips, may be observed while the horse is breathing.The rear portion is cloudy as indicated at 226. The precise areas canvary substantially from those shown in the drawings, and there need notbe a definite line of demarcation, although one is indicated in thedrawings. There can simply be a fading from the clear portion into thecloudy portion. An integral harness anchoring bar 228 is spaced out fromthe surface of the mask on either side thereof and generally proximateto the gasket 98 k for receiving a portion of the harness 36 k foranchoring the mask on the horse's head. The gasket 98 k is preferably ofthe zig-zag rubber type as previously shown and described in FIGS. 6-8for forming a seal to the horse's head, which both seals and iscomfortable to the horse. Alternatively, the gasket or seal could be ofthe pneumatic type as shown in FIG. 13. The important thing is that thegasket or seal seals the mask to the horse's head so that there is noleakage to or from the mask. This is important from a medicalstandpoint, and is also important from an equine behavioral standpoint.Horses are very sensitive to air movement over and along their heads,and a horse could be easily “spooked” by unwanted air movement along thehead.

[0101] At the lower and frontal portion of the mask there is provided ahand grip 130 k of hollow box-like formation, having elongated grooves128 therein extending substantially longitudinally of the hand grip.These grooves afford better gripping for an attendant's hand, and alsoprovide some rigidification if it is assumed that the hand grip 130 k ishollow. It is not imperative that the hand grip be hollow, but from aweight standpoint it is preferably so. The hand grip is provided alongits upper edge with a flange or wall 230 extending outwardly in bothdirections from the box-like hand grip 228. The hand grip itself liessubstantially on a median vertical plane of the mask. The lower frontportion 132 of the hand grip is preferably rounded for safe gripping bythe trainer or other attendant.

[0102] The upper portion of the mask is provided with a planar plate 234of substantially square configuration, but with rounded upper corners236, and with a lower tab or tongue portion 238 extending down to theflange or wall 230. The plate 234 is formed integrally with theremainder of the mask, and is provided near the upper portion thereof inhorizontally aligned array with a central aperture 240, and two sideapertures 242. These apertures are circular in outline, and each isprovided outwardly of its perimeter with a pair of arcuate slots 244having enlarged holes 246 at the lead ends thereof. The entire plate 234is surrounded by a peripheral, shallow upstanding flange 248.

[0103] An aerolization chamber 48 k is in substantially verticalposition when a mask is worn on the front portion of the horse's head. Awell 60 k is disposed above the aerolization chamber 48 k and opensupwardly through a shaped opening 50 in the top wall 252 above theaerosolization chamber. The entire wall 252 as well as theaerosolization chamber is formed of a resilient plastic, and the shapingof the aperture or opening 250 allows inwardly projecting portionsthereof to grip a metered dose inhaler (MDI) 62 with a nozzle 68 thereofextending through an opening 254 in a support member 256 to allow thedischarge spray 66 from the cartridge 62 to expand and aerosolize withinthe chamber 48 k.

[0104] The bottom wall 258 of the chamber 48 k is spaced somewhat abovethe wall 200 at the top of the hand gripping piece 130 k to permit air,as indicated by the arrow 260, to pass between the walls 230 and 258through a one-way valve 262. The valve has downward projections 264passing through slots similar to the slots 244 previously mentioned tohold the valve in mounted position over an opening in the bottom wall258. The structure of the one-way valve will be described morespecifically hereinafter, but it is to be understood that it permits airto enter in the direction of the arrow 260, but not to exit in theopposite direction therefrom.

[0105] A similar one-way valve 266 having downward or perpendicularprojections 268 thereon is mounted over the hole 240 in the plate 234,by means of projections 268 extending through the enlargement or holes246 at the end of the slot 244 adjacent the hole 240, the one-way valvethen being twisted in a counterclockwise position to lock in place. Itwill be understood that the projections 268 have enlarged outer endswhich pass through the holes 246, and then lock behind the plate 234 tohold the one-way valve in place. The one-way valve 266 permits air andmedication to pass into the mask 38 k in the direction indicated by thearrow 270.

[0106] As will be seen particularly in FIG. 23 the aerosolizationchamber 48 k has wing-like flanges 272 that extend in a common plane,but in opposite directions therefrom, to align in contact with themounting plate 234, being shaped to fit within the flange 248 about theperiphery of the plate 234. The exhalation valves 46 k are similar tothe valves 262 and 266 previously discussed, permitting exhalation ofair from the mask, but not permitting entrance of air into the mask uponinhalation. These one-way valves, to be disclosed in detail hereinafter,are provided with extensions or projections which pass through arcuateslots in the flanges 272, and then through the arcuate slots 244,including the enlarged holes 246, in the plate 234, whereby the valvesserve not only as one-way exhalation valves, but also as fasteningmembers to secure the flanges 272 and the aerosolization chamber 48 k inplace on the plate 234.

[0107] The aerosolization chamber 48 k will best be understood withreference to FIG. 26, along with FIGS. 23 and 24. The portion of theaerolization chamber receiving the spray 66 will be seen to be ofgenerally U-shaped outline, providing a cavity 274 into which the spray274 expands. The wings will be seen to have four pegs 276 extendingrearwardly perpendicularly from the wings 272, and respectively receivedin holes 278 (FIG. 25) in the mounting plate 234. The apertures 280 inthe wings 272 which overlie the apertures 242 in the mounting plate 234in alignment therewith are seen in FIG. 26, along with the arcuatelocking slots 282 with the entering end enlargements 284. Similarly, theaperture 286 receiving the inhalation valve 262 is shown in FIG. 26,along with the arcuate locking slots 288 within enlarged entering end290. Triangular walls 292 depending from the side walls of theaerosolization chamber 48 k below the bottom wall 258 thereof will beseen to abut the wall 230 at the top of the hand grip 232, defining withthis wall a mouth 294 through which air (as indicated by the arrow 260in FIG. 24) enters to pass through the inhalation valve 262.

[0108] The upper wall 252 is provided with a depending wall 296 oneither side thereof which is substantially U-shaped in cross section. Awall 296 has extending triangular sections with terminating edges 300which lie against the upper to forward portion of the mask for bestsupport of the upper portion 302 which holds the MDI canister 62. Atransverse bracing wall 304 may also be provided. Many parts of theaerolization chamber 48 k will readily be understood as being formedintegrally, with other parts such as the raised portion 302 beingpreferably formed separately and secured to the remainder thereof by anyknown technique, such as solvent or sonic welding.

[0109] Variations of Tenth Embodiment

[0110] 1. First variation (FIGS. 27 and 28). A variation is shown inFIG. 27 and 28, in which a plate 306 is secured to the mounting plate234, previously disclosed. This plate 306 is secured by means ofexhalation valves 46 k as previously discussed in connection with thestructure for mounting the aerosolization chamber 48 k. Rather than theprovision of the one-way inhalation valve 266, there is provided amounting disk 308 secured in the same way to the mounting plate 234 inalignment with the inhalation aperture 240 by means of extending pinshaving enlargements on the ends thereof, and extending through themounting slots 244. The mounting disk 308 has a plastic integral tube310 extending perpendicular to the plate 306. This tube 310 is of properdiameter to accept a conventional corrugated hose for a small volumenebulizer, or an ultrasonic nebulizer, or for oxygen supply. It will beunderstood that in accordance with the principles of the presentinvention an aerolization chamber could be provided in combination witha nebulizer or oxygen supply system. As will readily be understood theone-way exhalation valves 46 k secure the plate 306 to the mountingplate 234 generally as previously described.

[0111] 2. Second variation (FIG. 29). A further modification of theinvention is shown in FIG. 29 in which the plate 306 again is providedwith the one-way exhalation valves 46 k, which again mount the plate 306on the mounting plate 234. A distinction is that a ring 312 mounts onthe plate 306 in the same manner as the mounting disk 308 in theembodiment of FIG. 27 and 28, this ring being spanned by a rubber orplastic membrane 314 having a generally oval or elliptical opening 316therein for receipt of the exit portion of a metered dose dry powderinhaler.

[0112] 3. Third variation (FIG.30). FIG. 30 is generally similar to FIG.28, and the same numerals are used for identifying parts. Thedistinction resides in the provision of an oxygen diluter unitcomprising a corrugated hose or tubing 318 having a diluter unit 320 atthe outer end thereof having an axial oxygen receiving connector 322 atthe outer end thereof, and having a lateral window 324 for receivingambient air. Conventional means is provided for determining the degreeof opening or closure of the window 324 to admit diluting air into theoxygen supply through the connector 322.

[0113] 4. Fourth variation (FIG. 31). A further modification of theinvention is shown in FIG. 3l which superficially resembles FIG. 23.However, in this instance the upper portion 302 is omitted from thechamber 46 l, the number in this case being modified since the chamberno longer serves the purpose of aerosolization. The top wall 256 l ofthe chamber is a solid wall, and not apertured for receipt of the nozzleor valve of an MDI canister. Similarly, the bottom wall, although notshown, is also solid or continuous. A replaceable filter 326 is receivedin an opening 328 in the side wall of the chamber 461 so that the horsemay receive filtered air upon inhalation.

[0114] Valve Structures of Tenth Embodiment (FIGS. 32-34)

[0115] The structure of the one-way valve, exhalation valves 46 k beingchosen for illustration, is shown in detail in FIGS. 32-34. FIG. 32 willbe seen to be quite similar to FIG. 27, but from a different angle, andon an enlarged scale to show details of importance. FIG. 32 shows theexhalation valves as assembled on the plate 306. FIG. 33 is an uprightview of an exhalation valve 46 k, FIG. 33(a) being an assembled view ofthe valve, while FIGS. 33(b), (c) and (d) are exploded views. FIG. 34ais another assembled view of the valve 46 k, but in inverted position.FIGS. 34b, 34 c, and 34 d are similar to FIGS. 33b, 33 c, and 34 d, butwith the parts in relatively inverted position.

[0116] The exhalation valve 46 k consists of three parts joined togetherto act as a functional entity. The first or base part comprises a spider333, which includes a peripheral ring or flange 332 relieved at twolocations 334 which are 180° apart. An annular flange 336 upstands fromthe inner edge of the ring 332, and a pair of locking legs 338 dependbelow the ring 332 and are provided with outwardly directed feet 340.The feet are parallel to the ring 332, and both the legs 338 and thefeet 340 are of substantially the same arcuate extents as the gaps 334in the ring 332.

[0117] A flat ring 342 tops the arcuate wall 336, and extends inwardlytherefrom. The ring 342 is provided with a large central aperture 344which is bridged by two right angle backup arms, and by two narrowerarms 348 which are at right angles to one another, but at 45° angles tothe relatively wider arms 346. All of the arms are coplaner with thering 342. Finally, depending walls 350 underlying the ring 342, andcooperating with the ring 332 in the same plane thereas definerectangular areas with arcuately elongated apertures 352 extendingthrough the ring 342.

[0118] All parts of the spider 330 as just described are integrallymolded of a suitable plastic resin.

[0119] Each exhalation valve 46 k is of three-piece construction, thespider just described being the first piece. The second piece is aflexible diaphragm 354 which preferably is made of a rubber or plasticmaterial. The diaphragm is provided with right angularly disposed slits356 disposed diametrically of the diaphragm. The diaphragm is furtherprovided outwardly of the slits 356 with arcuately elongated slots orholes 358 through the diaphragm. As best may be seen by comparison ofFIGS. 33b and c the diaphragm lies flat on top of the spider 330,particularly the upper ring 342 thereof. The holes 358 in the diaphragmalign with the holes 352 in the ring 342, and the slits 356 overlie andare centered on the relatively wide arms 346 of the spider. The narrowerarms 348 are centered beneath and support the flaps 360 of the diaphragmdefined by the slits 356.

[0120] A third and final part of the exhalation valve comprises a cap362 including a horizontal, flat ring 364 and a depending peripheralwall 366. This peripheral wall and the periphery of the spider ring 332may be axially lined or knurled to facilitate gripping and twistingthereof. The cap further includes four pairs of depending studs or legs368 having outwardly directed teeth 370 with inclined lower faces. Thesets of teeth are disposed at 90° to one another, and hold the threeparts of the valve together. The diaphragm 354 is laid on top of thespider as noted before, with the apertures 358 therein aligned with theapertures 352 of the spider, and the slits 356 centered on therelatively wide arms 346. The cap 362 then is positioned over thediaphragm and spider, and pressed down. The pairs of legs 368 passthrough diaphragm holes 358 and snap through the holes 352 in the spiderring 342, and snap out beneath this ring to hold the three parts inassembled relation.

[0121] The exhalation valves are installed by inserting the feet 340through the enlargements, for example the enlargements 284 in theflanges 272 (FIG. 26), and also through the enlargements 246 of theslots 244 of the mounting plate 234 (FIG. 25), and then twisting thevalves. The valves thus are used for assembling the replaceable parts,such as the aerosolization chamber, etc. of FIGS. 23, 24 and 16, or theadapting plates 306 of FIGS. 27-30, and they also serve as the necessaryone-way exhalation valves. As will be apparent, the diaphragm flaps 354are free to flex outwardly away from the spider 330, but cannot flexinwardly because of the relatively wide arms 346 underlying the slits356, and the relatively narrow arms 348 underlying the flexible flaps ofthe diaphragm. Not only are the valves dual purpose in permittingexhalation, and in holding parts together, but they are readilyremovable for cleaning (note that the horse will exhale vapor and mucusthereon) or for substitution of parts, such as the plate 306 for theaerosolization chamber, or for repair, such as replacement of adiaphragm.

[0122] The inhalation valves are similar to the exhalation valves, buthave the position of the spider and the diaphragm reversed to permitinward air flow, but to prevent outward air flow.

[0123] The mask as shown and described in connection with FIGS. 23-34 ismolded of a suitable plastic material, as heretofore noted. An acrylicresin is satisfactory for most purposes, although a polycarbonate resinis stronger and more resilient, and would be preferably for use instable where the mask might be knocked to the ground and stepped on. Themask may vary quite considerably in size in different models dependingon the horse with which it is to be used, and for one specificillustration the distance from the front of the handle or hand gripportion 232 to the back of the seal or gasket 98 k is 7 inches, the topto bottom dimension across the seal is 8 inches, and the lateraldimension across the mounting plate 234 is 5 inches. The rubber sealprovides a considerable adaptability, whereby only a few sizes of maskshould be necessary to accommodate a large number of horses, with norequirement for an individual size for each horse. The clear ortransparent forward position of the mask is advantageous as thetechnician may watch the horse's nostrils for discharge of medicationinto the aerosolization chamber toward the end of exhalation and beforethe start of inhalation. As heretofore noted, various other devices maybe applied in place of the aerosolization chamber due to the dual use ofthe exhalation valves.

[0124] Various changes in specific structure will no doubt occur tothose skilled in the art, and will be understood as forming a part ofthe present invention, insofar as they fall within the spirit and thescope of the appended claims.

The invention is claimed as follows:
 1. An improved therapy deliverysystem for an animal having a snout, for use with (a) a source forproviding an aerosol of medication; (b) an aerosolization holding devicehaving: (i) a closed chamber; (ii) an inlet for receiving the aerosol ofmedication from said source into said chamber; (iii) an exit passagethrough which said aerosol can exit said chamber; and (iv) an exit valvelocated in said exit passage to permit flow in a direction from saidchamber and prevent flow into said chamber through said exit passage;wherein the improvement comprises: a mask comprised of: (a) a mask bodysized and adapted to conform to a forward portion of a head of an animaland to cover at least an animal's nostrils; (b) a fitting defined aroundan opening through said mask, an inlet communicating with the exitpassage of the aerosolization chamber; (c) an exhalation valve in anopening through said mask, said exhalation valve adapted to permit airflow through said opening upon exhalation into said mask so as to permitan animal wearing said mask to exhale air through said opening, and toprevent air flow through said opening upon inhalation.
 2. A mask for ananimal having a snout comprising: a mask body sized and adapted toconform to a forward portion of a head of an animal to cover at leastthe animal's nostrils; a chamber adjacent said mask body, said chamberhaving a support wall with an opening through which a source of aerosolis provided, a wall having a one-way valve located in an openingtherein, said chamber communicating with said mask body via an openingin a plate thereof; first and second exhalation valves located inopenings through said mask body, said openings adjacent the animal'snostrils, said first and second exhalation valves adapted to prevent airflow in a direction from outside said mask body into said mask bodythrough said openings, but permit air flow from inside said mask bodyout of said mask body through said openings; and a gasket located alonga rear edge of said mask body.
 3. The mask of claim 2 wherein saidopening comprises the only inlet through which ambient air can enterinto said mask body.
 4. The mask of claim 2 wherein said openingscomprise first and second openings, wherein said first of said openingsis located on one side of said opening and adjacent one of the animal'snostrils and said second of said openings is located opposite from saidfirst opening on another side of said opening adjacent the other of theanimal's nostrils.
 5. The mask of claim 2 further including: whereinsaid gasket comprises a close fitting seal whereby leakage of air intosaid mask body except through said opening is reduced.
 6. The mask ofclaim 2 wherein said mask body is transparent.
 7. A mask for an animalhaving a snout comprising: a mask body sized and adapted to conform to aforward portion of a head of an animal covering at least the animal'snostrils; a mask inlet communicating with a source of aerosol medicationand also comprising a means for providing breathing air to the animal,wherein said mask inlet comprises the only inlet into said mask body; aone-way inhalation valve located with respect to said mask inlet toprevent flow of air from said mask body; and first and second exhalationvalves located in openings through said mask body, said openingsadjacent the animal's nostrils, said first and second exhalation valvesadapted to prevent air flow in a direction from outside said mask bodyinto said mask body through said openings, but permit air flow frominside said mask body out of said mask body through said openings. 8.The invention of claim 7 wherein said openings comprise first and secondopenings, wherein first of said openings is located on one side of saidmask inlet and adjacent one of the animal's nostrils and said second ofsaid openings is located opposite from said first opening on anotherside of said mask inlet and adjacent the other of the animal's nostrils.9. The invention of claim 7 further including: a close fitting gasketlocated along a rear edge of said mask body and conforming in shape toan animal's head, whereby leakage of air into said mask body exceptthrough said mask inlet is reduced.
 10. The invention of claim 7 whereinsaid mask body is transparent.
 11. A mask for an animal having a snoutcomprising: a mask body sized and adapted to conform to a forwardportion of a head of an animal to cover at least the animal's nostrils;a mask inlet communicating with a source of aerosol medication, whereinsaid mask inlet comprises the only inlet into said mask body; a one-wayinhalation valve located in said mask inlet to prevent flow of air fromsaid mask body into said source of aerosol medication; first and secondopenings located through said mask body, wherein said first of saidopenings is located on one side of said mask inlet adjacent one of theanimal's nostrils and said second of said openings is located oppositefrom said first opening on another side of said mask inlet adjacent theother of the animal's nostrils; and a first exhalation valve located insaid first opening through said mask body and a second exhalation valvelocated in said second opening through said mask body, said first andsecond exhalation valves adapted to prevent air flow in a direction fromoutside said mask body into said mask body through said openings, butpermit air flow from inside said mask body out of said mask body throughsaid openings.
 12. The invention of claim 11 further including: a closefitting gasket located along a rear edge of said mask body andconforming in shape to an animal's head, whereby leakage of air intosaid mask body except through said mask inlet is reduced.
 13. Theinvention of claim 11 wherein said mask body is transparent.
 14. A maskfor an animal having a snout comprising: a mask body sized and adaptedto conform to a forward portion of a head of an animal and to cover atleast the animal's nostrils; a first opening providing an air inlet intosaid mask body; a one-way inhalation valve located with respect to saidfirst opening to prevent flow of air from inside said mask body throughsaid oneway inhalation valve; a means for providing aerosol medicationfrom a source thereof to said mask body, said providing means comprisinga second inlet through which an aerosol can be provided to said firstopening; and first and second exhalation valves located in third andfourth openings through said mask body, said third and fourth openingsadjacent the animal's nostrils, said first and second exhalation valvesadapted to prevent air flow in a direction from outside said mask bodyinto said mask body through said openings, but to permit air flow frominside said mask body out of said mask body through said openings. 15.The invention of claim 14 wherein said third opening is located on oneside of said mask inlet adjacent one of the animal's nostrils and saidfourth opening is located opposite from said third opening on anotherside of said mask inlet adjacent the other of the animal's nostrils. 16.The equine mask of claim 14 wherein said mask inlet comprises the onlyinlet into said mask body.
 17. The invention of claim 14 furtherincluding: a close fitting gasket located along a rear edge of said maskbody and conforming in shape to an animal's head, whereby leakage of airinto said mask body except through said mask inlet is reduced.
 18. Theinvention of claim 14 wherein said mask body is transparent.